Can anyone with "Active Cruise Control with Stop&Go" describe what happens when the front sensor is obstructed? Does the system scale back to conventional cruise control, or do you lose any/all cruise control until the sensor is cleared?

Can anyone with "Active Cruise Control with Stop&Go" describe what happens when the front sensor is obstructed? Does the system scale back to conventional cruise control, or do you lose any/all cruise control until the sensor is cleared?

What do you mean by obstructed? You are going to cover the sensor housing with something or you mean there is some small wall in the way?!?

Stop and go ACC on most vehicles uses a combination of forward facing radars and a forward facing camera, i.e. a sensor fusion algorithm. The radars don't work well once the vehicle comes to a stop (or at low speed) and is where the camera works best. The camera is usually mounted in the rear-view mirror housing. I think it's also used for the auto-high beam.

Can anyone with "Active Cruise Control with Stop&Go" describe what happens when the front sensor is obstructed? Does the system scale back to conventional cruise control, or do you lose any/all cruise control until the sensor is cleared?

What do you mean by obstructed? You are going to cover the sensor housing with something or you mean there is some small wall in the way?!?

Stop and go ACC on most vehicles uses a combination of forward facing radars and a forward facing camera, i.e. a sensor fusion algorithm. The radars don't work well once the vehicle comes to a stop (or at low speed) and is where the camera works best. The camera is usually mounted in the rear-view mirror housing. I think it's also used for the auto-high beam.

I'm not sure what the BMW system uses, but my first gen Chrysler 300C in 2008 used a Hella supplied LIDAR state as the sole sensor. That was easily blocked by either snow accumulation or even heavy rain or direct sunlight, as typical for a LIDAR system. When it was blocked, there was no cruise control at all. It was bad enough that they eventually released a software update that allowed you to hold the cruise control switch to enable legacy cruise control mode.

Usually stop and go systems, as you mentioned, combines two sensor technologies. However, i would still expect that if either sensor reports a fault, the entire system will refuse to operate

If something happens to it you won't have any cruise control at all, just a warning message if you try to engage it.

+1
I experienced that on the Autobahn a few days ago during snow fall. The radar got all covered by snow after a few miles ACC stopped working. Unfortunatelly "normal" cruise control also won't work.
Then I stopped and cleaned the radar, but it got covered by snow again after a few miles and ACC stopped working again.

This is a bit of a pain, because it means that in practice you won't have crusie control during "heavy" snow fall.
Still the driving conditions would allow to drive with Cruise Control activated.(Roads where just wet, not covered by snow nor ice)

I was a bit surprised that normal Cruise Control didn't work in this situation, as it is just holding a defined Speed. But I think they made it that way because "normal" Drivers could get confused by ACC suddenly working different as they are used to. (Although the Driver gets display message that ACC is not working)

+1
I experienced that on the Autobahn a few days ago during snow fall. The radar got all covered by snow after a few miles ACC stopped working. Unfortunatelly "normal" cruise control also won't work.
Then I stopped and cleaned the radar, but it got covered by snow again after a few miles and ACC stopped working again.

This is a bit of a pain, because it means that in practice you won't have crusie control during "heavy" snow fall.
Still the driving conditions would allow to drive with Cruise Control activated.(Roads where just wet, not covered by snow nor ice)

I was a bit surprised that normal Cruise Control didn't work in this situation, as it is just holding a defined Speed. But I think they made it that way because "normal" Drivers could get confused by ACC suddenly working different as they are used to. (Although the Driver gets display message that ACC is not working)

Probably, people could get confused if the car would brake by itself or not so I have no problem really with it not working like a normal CC in these conditions even though it most likely could if they allowed it. Maybe it is possible to code.

It really is a shame that the ACC Sensor doesn't have any heating. Just a little bit of too warm + snowfall and you have a blocked sensor.

When it gets blocked the ACC just goes standby. It is still on, but won't set. You need to scrub the snow off to get it running, but still the same problem after few kilometres.

However, at least in my F31, you can switch to normal cruise control by pressing the ACC distance buttons (closer or further, no difference) for ~3 seconds. And this works also, when you have a "blocked sensor" -error on.

you can also switch between ACC and normal-CC with the same manouver. Just when you go from CC to ACC you just have to tap the distance buttons.

It really is a shame that the ACC Sensor doesn't have any heating. Just a little bit of too warm + snowfall and you have a blocked sensor.

When it gets blocked the ACC just goes standby. It is still on, but won't set. You need to scrub the snow off to get it running, but still the same problem after few kilometres.

However, at least in my F31, you can switch to normal cruise control by pressing the ACC distance buttons (closer or further, no difference) for ~3 seconds. And this works also, when you have a "blocked sensor" -error on.

you can also switch between ACC and normal-CC with the same manouver. Just when you go from CC to ACC you just have to tap the distance buttons.

…at least in my F31, you can switch to normal cruise control by pressing the ACC distance buttons (closer or further, no difference) for ~3 seconds. And this works also, when you have a "blocked sensor" -error on.

you can also switch between ACC and normal-CC with the same manouver. Just when you go from CC to ACC you just have to tap the distance buttons.

Ford lets you toggle their active cruise to conventional-style cruise… I can only hope my future 2014 F30 will let me do the same!

Well, it will switch off automatically when ASC is activated.
Which makes sense as you could also be driving on wet road with ACC on and run into Aquaplaning.
Sure I would not activate ACC when there is already snow on the street. That's one of the moments where active driving is needed.

+1
I experienced that on the Autobahn a few days ago during snow fall. The radar got all covered by snow after a few miles ACC stopped working. Unfortunatelly "normal" cruise control also won't work.
Then I stopped and cleaned the radar, but it got covered by snow again after a few miles and ACC stopped working again.

This is a bit of a pain, because it means that in practice you won't have crusie control during "heavy" snow fall.
Still the driving conditions would allow to drive with Cruise Control activated.(Roads where just wet, not covered by snow nor ice)

I was a bit surprised that normal Cruise Control didn't work in this situation, as it is just holding a defined Speed. But I think they made it that way because "normal" Drivers could get confused by ACC suddenly working different as they are used to. (Although the Driver gets display message that ACC is not working)

Well, it will switch off automatically when ASC is activated.
Which makes sense as you could also be driving on wet road with ACC on and run into Aquaplaning.
Sure I would not activate ACC when there is already snow on the street. That's one of the moments where active driving is needed. ��

My ACC also goes down as soon as it is snowing. Why can't they put the sensor behind the grill instead? Less slush from the road. Also the sensor doesn't look that great with Msport.

My 300C had it mounted behind the grill and that does not really help at all. It still gets occluded by snow accumulation on the grill quite readily.

Also, when put there, the car loses peripheral vision of vehicles around you, which leads to much more undesired emergency braking around corners, where the car thinks that the car in the lane next to you appeared out of nowhere.

Well, it will switch off automatically when ASC is activated.
Which makes sense as you could also be driving on wet road with ACC on and run into Aquaplaning.
Sure I would not activate ACC when there is already snow on the street. That's one of the moments where active driving is needed.

Quote:

Originally Posted by BavarianFanatic

This is a very disturbing statement.

Why? What I mean is ACC will switch of as soon as Stability Control (ASC) detects a critical situation and starts stabilizing the car. So if you drive 40 mph on a snow road and the car will loose traction or starts shifitng away, ACC is deactivated.
The car will loose speed (unless the Driver pushes the gas pedal).

Another disturbing thing about the ACC is when I charge my phone via USB and listen to music using the AUX. When the car brakes (with ACC active) an annoying white noise is transferred to the speakers. If I only connect the AUX and don't connect the USB to charge the phone there is no interferrence. It happends as the car infront gets too close and my car stopps accelerating and starts braking.